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The Single UNIX &reg; Specification, Version 2<br>
Copyright &copy; 1997 The Open Group

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<h4><a name = "tag_000_005_239">&nbsp;</a>NAME</h4><blockquote>
free - free allocated memory
</blockquote><h4><a name = "tag_000_005_240">&nbsp;</a>SYNOPSIS</h4><blockquote>
<pre><code>

#include &lt;<a href="stdlib.h.html">stdlib.h</a>&gt;

void free(void *<i>ptr</i>);
</code>
</pre>
</blockquote><h4><a name = "tag_000_005_241">&nbsp;</a>DESCRIPTION</h4><blockquote>
The
<i>free()</i>
function causes the space pointed to by
<i>ptr</i>
to be deallocated; that is, made available for further allocation.
If
<i>ptr</i>
is a null pointer, no action occurs.
Otherwise, if the argument does not match a pointer earlier
returned by the
<i><a href="calloc.html">calloc()</a></i>,
<i><a href="malloc.html">malloc()</a></i>,
<i><a href="realloc.html">realloc()</a></i>
or
<i><a href="valloc.html">valloc()</a></i>
function, or if the space is deallocated by a call to
<i>free()</i>
or
<i><a href="realloc.html">realloc()</a></i>,
the behaviour is undefined.
<p>
Any use of a pointer that refers to freed space causes undefined
behaviour.
</blockquote><h4><a name = "tag_000_005_242">&nbsp;</a>RETURN VALUE</h4><blockquote>
The
<i>free()</i>
function returns no value.
</blockquote><h4><a name = "tag_000_005_243">&nbsp;</a>ERRORS</h4><blockquote>
No errors are defined.
</blockquote><h4><a name = "tag_000_005_244">&nbsp;</a>EXAMPLES</h4><blockquote>
None.
</blockquote><h4><a name = "tag_000_005_245">&nbsp;</a>APPLICATION USAGE</h4><blockquote>
There is now no requirement for the implementation to support
the inclusion of
<i>&lt;malloc.h&gt;</i>.
</blockquote><h4><a name = "tag_000_005_246">&nbsp;</a>FUTURE DIRECTIONS</h4><blockquote>
None.
</blockquote><h4><a name = "tag_000_005_247">&nbsp;</a>SEE ALSO</h4><blockquote>
<i><a href="calloc.html">calloc()</a></i>,
<i><a href="malloc.html">malloc()</a></i>,
<i><a href="realloc.html">realloc()</a></i>,
<i><a href="stdlib.h.html">&lt;stdlib.h&gt;</a></i>.
</blockquote><h4>DERIVATION</h4><blockquote>
Derived from Issue 1 of the SVID.
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UNIX &reg; is a registered Trademark of The Open Group.<br>
Copyright &copy; 1997 The Open Group
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